Hardgrove Grindability Tester

Hardgrove Grindability Tester – Precision Coal Pulverization Measurement

The Hardgrove Grindability Tester is an essential tool for determining the relative ease of coal pulverization compared to standard coal samples. Designed in accordance with ASTM D409 and ISO 5074 standards, this machine reliably calculates the Hardgrove Grindability Index (HGI), a critical measure for assessing the energy required for coal grinding or the yield for a specific energy input. Its robust design and precise operation make it a trusted choice in laboratories and industrial settings.

How It Works:

The Hardgrove Grindability Tester operates by grinding a 50g sample of coal (sized between No. 16–No. 30 sieves) with eight 1in (25.4mm) polished steel grinding balls. The coal is placed in a stationary bowl with a machined circular track, while a rotating upper grinding ring (matching the track) drives the grinding balls at 20rpm. A fixed load of 64lb (29kg) is applied to the motor-driven spindle of the upper ring to ensure consistent pressure. After 60 rotations, the tester automatically stops, and the degree of grinding is measured by sieving the material through a No. 200 sieve. This precise process delivers reliable HGI values, critical for evaluating coal quality and optimizing grinding operations.

Why Choose This Tester?

The unit is constructed from durable steel and cast iron, ensuring long-lasting, maintenance-free operation. It is designed for ease of use, with all essential grinding elements and accessories included, making it an indispensable tool for coal testing laboratories, power plants, and industries relying on accurate coal analysis.

Calibration and Sample Preparation:

To ensure accurate results, new Hardgrove units require calibration using Reference Samples with HGI values of approximately 40, 60, 80, and 100, which are available separately. Additionally, a Motorized Disk Mill (sold separately) can be used to prepare samples in compliance with ASTM specifications, ensuring consistent and reliable results.

Key Features:

• Reliable, maintenance-free operation with robust steel and cast iron construction.
• Meets ASTM D409 and ISO 5074 standards for grindability testing.
• Precise measurement of coal pulverization with automated operation.
• User-friendly design for consistent, repeatable testing.

Included Items:

• Hardgrove Grindability Tester (available in 115V/60Hz or 230V/50Hz models).
• Upper and lower grinding elements.
• 8 polished steel grinding balls (1in/25.4mm diameter).

Optional Accessories:

• Reference Samples: Four calibration samples with HGI values of approximately 40, 60, 80, and 100 for new unit calibration.
• Grinding Balls: Replacement steel grinding balls for long-term use.
• Motorized Disk Mill: For ASTM-compliant sample preparation.

Technical Specifications:

• Maximum Particle Size: 0.04in (1mm)
• Final Particle Size: 75µm
• Maximum Feed Capacity: 50g per batch
• Grinding Elements: Eight 1in (25.4mm) polished steel balls
• Electrical Requirements: 115V/60Hz, 5 Amps, 1 Phase
• Product Dimensions: 20 x 16 x 16in (508 x 406 x 406mm), WxDxH
• Weight: 180lb (81.65kg)
• Meets Test Methods: ASTM D409, ISO 5074

Applications:

• Power plants for assessing coal performance and energy efficiency.
• Laboratories conducting coal quality analysis.
• Industries requiring precise grindability testing for material processing.

The Hardgrove Grindability Tester is the ultimate tool for accurate, reliable coal grindability testing. Designed for durability and precision, it ensures your process runs smoothly while delivering actionable insights into coal quality and performance.